


the logical way to get exactly what you want

by fascinationex



Series: transformers fics by fascinationex [9]
Category: Transformers - All Media Types, Transformers: Prime
Genre: Bottom Shockwave, Consentacles, M/M, Prompt Fic, Smut, Sticky Sexual Interfacing, Tentacles
Language: English
Status: Completed
Published: 2019-12-07
Updated: 2019-12-07
Packaged: 2021-02-25 20:48:24
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,359
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21701713
Author URL: https://archiveofourown.org/users/fascinationex/pseuds/fascinationex
Summary: Shockwave gets railed by Soundwave's tentacle-cables. That's it. That's the plot.
Relationships: Shockwave/Soundwave
Series: transformers fics by fascinationex [9]
Series URL: https://archiveofourown.org/series/1311599
Comments: 8
Kudos: 195





	the logical way to get exactly what you want

**Author's Note:**

> I asked for smut prompts over [on twitter](https://twitter.com/fascination_ex/status/1202516023619883009) and people were kind enough to respond to me. This one is for a prompt from Twitter's @here_fanart: "Tfp soundwave using his tentacles to "sort of" forcefully fuck tfp shockwave..."

“Logically,” Shockwave said, in much the same tone as he might use to discuss meteorological conditions, “it will fit.”

He was holding one of Soundwave’s cables, which had previously been attached to a console in Shockwave’s laboratory. It was caught between two of the claws of his left hand.

For someone like Shockwave, whose processor functioned quickly and chewed ravenously through any data with which it was presented, it was easy to imagine multiple alternative uses for those cables. His valve was already warming when he said it. The sensitive, responsive systems began to build heat behind his thick and heavy armour. 

They were alone in the laboratory now, for once absent the interference of other officers. Like much of the ship this room was dark, illuminated by frustratingly low overhead lighting, the sickly glow of consoles, and the dim reflections of their own biolights. The Nemesis had not been constructed with any care for the clarity and accuracy of visual data.

Soundwave turned his helm toward Shockwave, which revealed only his blank, dark visor. He said nothing. 

At length, he withdrew his cable from Shockwave’s grasp. Shockwave allowed it to escape him, but Soundwave only brought it higher between them instead of pulling it back beneath his own plating. The cable’s tip hovered, still and held perfectly steady, at the same height as Shockwave’s single, huge optical lens. 

The cable was thin, dark and flexible, with glimpses of Soundwave’s own purple biolighting escaping between the short plates that covered it. Its head, which he displayed to Shockwave so pointedly, was thicker than the rest of the cable, and was ringed with thin metal claws intended to dig in, grasp and keep tight hold of whatever they met. They could spin fast enough to rip a mechanism’s plating, and that was only the most obvious danger. Within the ring of those vicious little tines were longer, gentler little tendrils – filaments capable of sliding into any receptive port and delivering both powerful shocks and insidious code.

As the cable hovered up between them, Soundwave allowed its graspers to flare out and spin. The noise filled the air: whirring, sharp and industrial. 

The message was clear: the cables were dangerous. 

Shockwave was not dissuaded. The fact of the danger was not a logical argument against his proposal. 

It was unclear if Soundwave was ignorant of this, or if he was dissembling to avoid giving offence with another, more personal rejection. In the first case, Shockwave would correct him; in the second case, Shockwave preferred direct communication to confusing discretion.

Shockwave queried: “For what purpose would you choose to damage me?”

He caught the cable with his left hand again. It hummed gently under his fingers, and twitched when he closed his grip around it. 

Despite that involuntary movement and how thin it seemed in his hand, he was under no illusion as to whether or not Soundwave had allowed it. Each of the cables was strong enough to pick up and physically hurl a sports car through a wall. Shockwave had observed this. At one point, he had measured their output. Soundwave was a specimen of no small interest – although his skill and temperament made him much more useful as a communications officer than a subject.

The thought of the sheer force they cables could bring to bear excited him. If Soundwave could be persuaded, those cables could make him feel very good. 

Hidden well behind his panel, the lowermost calipers of his valve gave a short, hopeful squeeze. It felt pleasant, making him even more aware of how very ready his frame already was, but it also emphasised the dull and empty ache. Shockwave wanted the cable in his hand to be buried deeply in his valve.

Soundwave’s visor remained blank, because he had no answer for Shockwave’s query. He gained nothing from injuring Shockwave. In fact, he benefited from Shockwave’s current position in the Decepticon command structure because Shockwave drew much of Starscream’s fickle attention.

That Soundwave knew this was certain, for he knew their first lieutenant better than Shockwave did. 

“Even had you something to gain from causing me damage,” said Shockwave, bringing his cannon-arm up and its outside plating fearlessly within range of Soundwave’s whirling cable tip, “the gain would not outweigh the logical ramifications of that course of action.” 

The spinning ceased. The drilling fell silent. And precisely as predicted, the dangerous spin of gleaming metal halted completely before inflicting so much as a scratch upon his plating, let alone true damage. 

Shockwave dipped the edge of the cannon’s barrel between the metal claws. The thin, delicate filaments separated around it, glowing softly with electricity. They were alive with energy even at rest, and they buzzed on his plating. The claws clenched and released with a soft echoing _clickclickclick_ , tapping gently on the plating. 

“Valve injuries are rarely fatal,” Shockwave noted. “It is unlikely that you could render me inoperable, but were you to damage me, I would become your enemy.”

Were he speaking to certain other Decepticons, Shockwave would have clarified his position on that point: he was not a desirable enemy. But with Soundwave, there was no need. He spoke little but he understood much.

Still. “The likelihood of such a series of events is low.” 

He paused, and then, with those crackling little filaments still buzzing fitfully against his cannon barrel, he added: “Logically, it will fit.”

Feeling it with his cannon, Shockwave’s processor was already extrapolating, with some accuracy, the possible sensation that would trigger when those little things touched the nodes in his valve. The very idea made an electric current shoot down the heavily-armoured circuitry of his spine. A minor alert flashed up: moisture, too, was gathering in his valve. His frame wanted to unlatch the panel covering it. He denied the request, but shifted on his feet to relieve the soft maddening throb of his valve's inner lining swelling and aching.

There was another long pause. Soundwave tilted his helm like a curious predator. 

It was a considering silence, and Shockwave judged himself more likely to get his way if he let it continue rather than interrupting. 

Finally, a sine wave described itself smoothly across the screen of Soundwave’s visor, mirroring Shockwave’s own voice, which he played right back to him: “ _Logically, it will fit._ ”

Shockwave nodded, satisfied that he had won Soundwave over. There was a full and eager throb between his hips, deep inside, where his ceiling node was. 

“Indeed,” he agreed, not sounding half as hungry and restless as he now felt. He squeezed Soundwave's cable gently in his fist. It made no response.

There was no need to leave the laboratory, and in fact Shockwave preferred to interface here – where his cameras and sensors were in operation and would enable him to reflect upon the heat, electrical and life activity of them both when he had the leisure time to do so. Instead he turned away from Soundwave and braced himself with his hands upon an unoccupied table and presented himself for Soundwave’s attention. 

His valve panel clicked and slid smoothly away, a microtransformation with only a very soft metallic sound behind it. 

Shockwave’s valve was a standard model. It was sensible, during the long years of war – not to mention of isolation and slow self-repair – to expend all efforts at upgrading upon his armour, the resilience of his internal mechanisms, and his own firepower. His interfacing equipment was a low priority, and remained only what he’d been forged with. The mesh and silicone and sensitive lining of his valve were very dark, and he knew his biolights and sensory nodes must be visible, glowing within. 

They would be pulsing softly to Soundwave’s optics, glowing brighter and dimmer in time with his spark. It was spinning more rapidly than usual beneath his heavily armoured chest plates. He was already excited enough that he could feel each whirl of his spark throbbing like a primitive drum in his valve.

He did not look back to see what Soundwave was doing. His visor would give nothing away, not even the zoom of his optics, and his body language would be as precisely, intentionally neutral as it ever was. There would be no point. 

“Proceed,” he said, when it seemed like Soundwave had to be waiting for something – either that, or he was merely taking his time to stare at Shockwave’s valve. Either seemed inimical to Shockwave's immediate goal. His valve was increasingly damp and warm, especially now that Soundwave had agreed and increased his anticipation to a new level. His valve craved the stimulation.

Soundwave didn’t make any sound of acknowledgement, but there was a soft hiss as the cable Shockwave had held moved quietly through the air in response. Shockwave relaxed minutely to hear it.

The head of the cable _tinked_ against the back of one knee joint and then crawled upward with the soft vibrating sigh of hard metal on metal. He was expecting it, but Shockwave still twitched when it slithered swiftly over his thigh, around the edge of his heavy plating, beyond the thick metal cords in the joint of his hip – and slid over the soft, warm lips of his valve instead.

It was a sensitive area – even merely the mesh and silicone, without stimulation to the nodes there that were designed to carry sensation, interpreted the touch with a sensitivity unmatched by the rest of his frame. Soundwave was just as precise with his cables as he was with his fingers. He turned the head of the cable deliberately away and stroked with its flexible body, dragging the smooth length along the dark valve lips.

Shockwave shuddered.

Soundwave must have been able to feel – or at least receive sensory data – from his cables, because he certainly registered the presence of heat and moisture within moments. Then the metal graspers clicked together, curled up politely in on themselves to make the intrusion as gentle as possible. It would still feel comparatively significant: Shockwave had not had a single thing in his valve in hundreds of years. 

The thick head of Soundwave's cable nudged inside, wiggling to push back the lips one side at a time. Shockwave's valve clenched down, calipers trying to clutch the intrusion, and the involuntary movement rubbed all of the nodes nearest the valve opening across the cool metal head. 

Shockwave grunted at the sudden bloom of sweet, warm sensation, and his fans kicked up predictably. It felt good. 

Soundwave did not pause. Silently, he used the flexibility of the cable to squirm the head deeper, until it pressed blissfully against the next set of calipers. 

Shockwave moaned aloud.

The cable did not feel like a spike. It was too flexible, too hard, and much too long, and although Shockwave had seen a great many spike mods pass through his laboratories, they were never like this. They weren't as strong, either -- few mechanisms could get the leverage with a spike that Soundwave had with his cables, and fewer still were as sturdy. Every movement felt powerful. 

And Soundwave, true to his prediction, did not dig and rip and drill violently. The cable moved slowly, graspers quiet, siding against the thick and swollen innermost lining of his valve. There was very little give in it. Its thin and flexible filaments stroked the innermost walls of his valve as it moved, seeking out the glowing, raised sensory nodes within. 

Shockwave's processor initially kept track of those nodes in minute detail, counting, assessing, but the tendrils were many and moved quickly, and each node that they found was rapidly overwhelmed. The cable itself crackled with power –he could hear it, and see the reflection of the excess light of it on the polished floor. Each new node it passed responded by flooding his sensory network with syrupy liquid pleasure. Each sensitive, throbbing little sensor was teased and rubbed and caressed with charge. It did a better job at overwhelming him than any excess of raw data.

Every part of his valve lit up as Soundwave's cable moved through it. And move it did: slow but unstopping, pushing aside each new set of calipers it encountered with whatever force was required, without regard for their resistance. It was relentless and his valve was forced to stretch to accommodate it, a circumstance that made him ridiculously, shamefully wet. 

Shockwave made a low, wordless sound, long and hard and shaking in time to the slow helpless shudders of his beautifully stimulated frame. This... Had been a good idea. It stood to reason: a significant majority of Shockwave's ideas were good.

Soundwave hit something particularly good, and he saw nothing but sparks for a moment, shivering. His ventilation system changed sounds as it clicked over to operate at a higher intensity.

"Ahh... like that," he said, and was gratified when Soundwave repeated precisely the same motion. He dug his fingers into the table and balanced more of his weight upon it. His knees felt like they might unhinge, although he had no significant warnings to suggest that it was a true risk.

He vented, blasting heat. The long, snake-like body of the cable felt good, solid and hard, rubbing against nodes left shockingly sensitive by the filaments at its tip. His valve produced more lubricant as it was stimulated, and the wet noises it made seemed very loud in the laboratory.

"More," he demanded, and Soundwave obliged. He took the statement literally. Another cable rasped gently against the first as it slid along its length. He felt the cool metal of it bump into the soft outermost surfaces of his valve. 

A long, thin tendril, crackling with raw energy, flicked against his anterior node. Shockwave grunted at the shock and the sudden intensity of it. When it withdrew he pressed closer, and as though encouraged by the invitation, it flicked out again. He groaned. Loudly.

The graspers of Soundwave's cable opened on one side, pressing gently then, opening the lips of his valve. The long, delicate filaments surged into the space it had opened, and the nodes there throbbed and surged with new power. His fans blasted hot air down upon the table, which only reflected it back at him. 

The area between his hips felt like a puddle of mercury, soft and warm, fluid and open. He opened his mouth to aid his ventilation, and each panting cycle of air came out with a low little moan. It would have seemed unnecessarily humiliating, had he not been flooded so beautifully with glowing, chemical pleasure.

The new cable surged inside while he was still reeling, and together the pair of them twisted and rubbed. Together they were thicker than most spikes, and moved independently, applying pressure in different places and with strange, writhing motions. 

His valve was stretching with each hard thrust, but it could not immediately accommodate both cables in comfort. It burned as he stretched, calipers rapidly rearranging themselves, microtransformations whirring quietly at his t-cog. The sheer thickness was almost unbearable against the tender and sensitive walls of his valve. 

But he was only getting wetter. He could hear it. And he could certainly feel it, clean up his spine, throbbing in all his circuitry.

It felt very, very good.

"Harder," he gasped, and Soundwave obliged, again: immediately, precisely. The tip of the cable inside Shockwave's valve rocked into his ceiling node hard, hard enough that his whole frame moved with it, shoved forward. 

He shouted. It was just noise, no words. He didn't even think in words.

His arms scraped across the surface of the table. The cannon left a gouge that would need to be buffed out. A third cable slithered around his waist, over his broad chest plates, and wrapped around him. He felt the pressure of it squeezing, tightening like a boa. He jolted, and then its tight harness heaved him back into the next thrust of the two buried inside him.

“Ah..!” Shockwave’s single, huge optic flickered erratically. His cries grew deeper, more forceful. 

The nodes in his valve were firing erratically, teased to overwhelming sensitivity and now pushed beyond their capacity by the forceful and punishing rhythm. 

" _Yes_!" he said, hard and short, and if anything this just encouraged Soundwave to go harder with him. The restraining cable around him held him still, forcefully, a band of durasteel around his chassis. 

The cables inside him pulled back, rubbing hard past every node in his valve, dragging their thicker heads across the frantic clenching of his calipers. He let out a low, broken groan which turned abruptly into a shout when they pushed back in, hard, relentless. One of the thick cable heads slammed again into his ceiling node, and Shockwave wailed, feeling his knees unhinge.

He did not fall as he had expected, for the cable wrapped around his body held him steady, squeezing tighter still, scraping against his armour as it twisted for a better grip. And then it was really rough: each movement shoved him forward and dragged him backwards, and all that held him still was Soundwave.

His valve loved it. He groaned helplessly with every forceful shove, limbs twitching convulsively, processor reeling. 

A warning flicked up, telling him that his coolant was too hot. He ignored it. His optic flickered and went dark. All he could see was sparks, anyway. 

Soundwave's cable slammed home again, hot and crackling tendrils crushed against his ceiling node. He made a sound like a sob, and his fingers flexed abortively, clutching at the cable around his chassis. "Yes..!"

He let out a scream when his frame finally convulsed in overload, biolights flickering erratically and optic completely dark.

His valve clenched down, hard, over and over, spasming wildly around the Soundwave’s cables, which – kept going, hard, shoving, punching deep, an unrelenting stimulation.

Every new slam against his ceiling node shot off another bright, hard, intense electric wave of pleasure. He grunted and groaned with it, straining against the vicelike grip of the cable wrapped around him.

He could feel pointless twitches, triggered by random electricity firing in his sensory system rather than his voluntary processor, shaking his limbs. Still Soundwave’s cables moved, forceful and unceasing, over and over, long and hard thrusts. 

They were still moving when he began to come down, with his optic blinking rapidly and his systems trying to reset. He panted through his mouth, desperate to circulate cooler air, even as his fans blasted waves of blistering heat out through his primary vents. 

The cables retracted, finally, dragging their grasping little tines out past each set of calipers, which tried to clench tightly closed again in their wake, with mixed success. They had been well and truly stretched. The nodes that weren’t numb were oversensitive, making Shockwave twitch and flinch as the cables came out. At last they came free with a wet, slick noise, leaving him exposed, valve swollen and – probably – drooling a little.

There was no more crashing metal, no more shamefully wet grinding. Just Shockwave’s fans, running at a scream in the dim laboratory. He let his valve panel slide shut, keeping any further lubricants inside his own armour.

He heard the soft sound of Soundwave’s plating shifting to allow the cables to fully retract. Then the _thud_ and the vibration of his footsteps in the floor. 

One hand, gentle, with long and precise fingers, lay upon his back carefully. 

Shockwave wondered if that was the kind of sentiment he had heard sometimes developed between mechanisms who interfaced with one another. Although the experience had been as good as he had predicted, and the overload had been deep and intense and left him reeling, he felt only a little for Soundwave in general and almost nothing for him personally. 

The possible ramifications of _Soundwave_ having an emotional investment, somehow, sprawled across his processor – 

A system ping requested only impersonal, medical information: was Shockwave recovering as expected?

Ah. 

He responded: Yes. He was. 

Soundwave’s hand withdrew. 

Shortly after, so did Soundwave himself. Just as Shockwave had predicted.

The doors hissed closed behind him, and Shockwave straightened, cleaned himself off, and returned to work. 

**Author's Note:**

> I'm not really sure how this went, characterisation wise, but I feel confident that I filled the prompt at least, phew.
> 
> If you liked something about this very irredeemable smut, please feel free to let me know in a comment. :)


End file.
